It has been conventional to determine the moisture content of objects for material samples by placement thereof in a well through which is passed microwave energy from a transmitting horn antenna to a receiving horn antenna. An excellent example of such a moisture detection apparatus is disclosed in U.S. Pat. No. 4,716,360 issued Dec. 29, 1987, entitled "Moisture Detector Apparatus and Method". As disclosed in said application, lenses may be associated with the transmitting and receiving antennas for providing improved transmission of the microwave energy through the sample.
It is further conventional to detect moisture content in bulk material as it is conducted through a sensing zone as by means of a conveyor belt or conveyor trough. One example of such an apparatus is disclosed in U.S. Pat. No. 3,460,030 of Donald C. Brunton et al.